Data is only used to temporarily hold information to be copied to the user
level, so it should be freed before leaving the function.
A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)
// <smpl>
@exists@
local idexpression x;
statement S,S1;
expression E;
identifier fl;
expression *ptr != NULL;
@@
x = \(kmalloc\|kzalloc\|kcalloc\)(...);
...
if (x == NULL) S
<... when != x
when != if (...) { <+...kfree(x)...+> }
when any
when != true x == NULL
x->fl
...>
(
if (x == NULL) S1
|
if (...) { ... when != x
when forall
(
return \(0\|<+...x...+>\|ptr\);
|
* return ...;
)
}
)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
static int dasd_ioctl_read_profile(struct dasd_block *block, void __user *argp)
{
struct dasd_profile_info_t *data;
+ int rc = 0;
data = kmalloc(sizeof(*data), GFP_KERNEL);
if (!data)
spin_unlock_bh(&block->profile.lock);
} else {
spin_unlock_bh(&block->profile.lock);
- return -EIO;
+ rc = -EIO;
+ goto out;
}
if (copy_to_user(argp, data, sizeof(*data)))
- return -EFAULT;
- return 0;
+ rc = -EFAULT;
+out:
+ kfree(data);
+ return rc;
}
#else
static int dasd_ioctl_reset_profile(struct dasd_block *block)